Discussion

Let us know what you think about any topic related to the Sierra Nevada Adaptive Management Project in the forums below. The Principal Investigators on the UC Science Team cannot answer every post, but they will read all comments in their areas, and respond to comments as a group at each quarterly meeting. We greatly value your input!

Owl Team response to questions from Steve Brink, 10/4/2012 by Kim_Ingram, at 3:33 p.m. on 4 October 2012,

The following are questions and responses regarding the CA spotted owl: Q1:Since 1993, the owl team stated that they have surveyed roughly 90% of the DSA each year. This was determined by placing a 1/2 mile buffer around each of the recorded survey points. Would it be possible to determine the % "covered" for each year 1986 through 1992 using the same methodology? If so, can the percentage of coverage be provided?

A1: We previously estimated the survey coverage on the Eldorado Density Study Area (EDSA) for the years 1989-1992:

1989: 78% 1990: 82% 1991: 86% 1992: 91%

Although the coverage was reasonably high in these years, many portions of the EDSA were only surveyed once per year from 1989-1992 because we did not have sufficient funding to hire an adequate number of technicians. This lack of survey effort made it more likely that we failed to detect owls that were actually present. 1993 was the first year that we conducted more than 1 survey at >90% of our survey stations.

Q2:Could the occupancy analysis be run on the owl sites that were first found in the study area from ~1986 through 1992? Has the occupancy rate for those owls sites dropped as well? Premise of question: The range -wide high reproductive year of 1992, (most likely due to abundance of prey and very mild spring weather) also lead to a high survival rate (young and adult) and potentially a population that was above the carrying capacity of the landscape. The population in 1993 with nearly 100% occupancy has been slowly adjusting back "down" to the “normal or potential” carrying capacity of this landscape.

A2: We appreciate Mr. Brink’s suggestion, but we currently lack the time and resources to pursue an occupancy analysis for the years 1986-1992. As we stated at the Owl IT meeting in August, we chose 1993 as the starting point of our analysis because it was scientifically defensible. In other words, a peer reviewer could assert that any observed occupancy trends were confounded by changes in survey effort if we used data prior to 1993.

We also question his premise that a single year (1992) of high reproductive output is still affecting our study population 20 years later. Spotted owls are long-lived, but with an annual survival rate of ≈ 0.83, it is unlikely that a birth pulse would continue to influence population trends 20 years after the pulse.

Questions for SNAMP Owl Team by Kim_Ingram, at 11:21 a.m. on 20 September 2012,

The following questions have been submitted by Steve Brink in response to the SNAMP Owl team's IT meeting in August 2012:

Q1)Since 1993, the owl team stated that they have surveyed roughly 90% of the DSA each year. This was determined by placing a 1/2 mile buffer around each of the recorded survey points. Would it be possible to determine the % "covered" for each year 1986 through 1992 using the same methodology? If so, can the percentage of coverage be provided?

Q2)Could the occupancy analysis be run on the owl sites that were first found in the study area from ~1986 through 1992? Has the occupancy rate for those owls sites dropped as well? Premise of question: The range -wide high reproductive year of 1992, (most likely due to abundance of prey and very mild spring weather) also lead to a high survival rate (young and adult) and potentially a population that was above the carrying capacity of the landscape. The population in 1993 with nearly 100% occupancy has been slowly adjusting back "down" to the “normal or potential” carrying capacity of this landscape.

Owl team response to questions from Steve Brink by Kim_Ingram, at 11:36 a.m. on 6 September 2012,

The following response is from the SNAMP Owl team to questions submitted by Steve Brink after the IT meeting of 8/23/2012:

Q1:Looking again at the Lambda graph, it’s interesting that the downward slope of the line is nearly constant. I should have thought about the 2001 Star Fire when Pat Ferrell, Eldorado NF Contracting Officer, asked a question about it. The Star Fire burned 16,900 acres in Aug-Sept. 2001, about 2,400 acres of which were on the Georgetown Ranger District. Following the fire, the USFS concluded that the two HRCAS, in which PAC055 and PAC075 were located, were essentially destroyed and recommended deleting both PACs from the Forest plan. Further, about 70% of the total acres burned in the Fire were of high severity. So, how is it that the Star Fire had absolutely no affect on the owls?

Response: First, recall that Doug noted that the estimates for lambda are based on model averaging (the average estimate of several models), which results in the smooth (“constant”) curve to which you refer. As long as the declining trend is not abrupt, it will appear relatively smooth despite slight variation in the annual estimates. Second, the two owl territories affected by the Star Fire were Regional territories, and the lambda analysis only included owl territories on the Density Study Area. Even if the two owl territories affected by the fire had been located on the Density Study Area, the observed impact would not have been dramatic because there are 45 owl territories on the density study area. In addition, we note that about 2,500 acres did burn on the Eldorado Density Study area during the Star Fire. This burn affected 3 owl territories on the density study, but all have been occupied at least once since the fire.

Q2: Because soil site classification could be used as a surrogate for the overall “primary productivity” of a forest, will the samples for the control and “treatment” areas be stratified? The premise being that owls in highly productive forests will perform better under both the control and “treatment” conditions, and likewise owls on less productive forests will underperform under control or treatment scenarios.

Response: This was suggested in the context of including “abiotic” factors as covariates in our analysis, which we think is a good idea. The idea of including soil type is a good one and we will consider that thoroughly for our list of covariates.

Q3: It’s still unclear to me why the Team is not opportunistic and looking to tease out why Owls had very high reproductive success in 1992. Using the 1993 data, and not using 1992, doesn’t seem intuitive given Rocky’s premise that CSO’s live a long time and have an evolutionary strategy that is opportunistic for reproduction. How can that be justified?

Response: The owl team has often wondered why there was such high reproduction in that year. The problem is that there is that there have been no other years such as 1992 to make comparisons. In other words, if you found several factors that were different in this year relative to other years, how would you distinguish which was consistent in terms of its importance to owls? One needs to have multiple examples of unique events to detect a pattern. In addition, 1993 was the first year that we had good aerial photography for the entire study area and adequate sampling effort to have confidence in detecting reproduction and a sufficient number of surveys over the entire study area. We note also, that unlike what was implied in our presentation, we do have air photos prior to 1993 but they are not seamless digitized photos as in 1993. Thus, it is quite time consuming to work with these other photos. It is important for the record to note that all of the effort to create vegetation maps by the owl team for the past dozen years in order to assess impacts has been done, until last year, without funding. That is, we have no allocated money to engage in this activity, but all the owl investigators have devoted their own time to create such maps because we realize the importance of the information. We continue to assess sources of air photographs that are easily used and welcome any help the SNAMP stakeholders are able to offer.

Q4: Given how robust the IPM is, why wouldn’t Doug include ALL of the owl data that the Team has including: 1)The discrepancies related to the 8 birds that were counted in the occupancy but not as part of the population and likewise the other 4 birds that resisted capture? 2)The 1992 reproduction data since it is congruent with Rocky’s premise that the evolutionary strategy of the owl is to be long lived and be opportunistic for reproduction? 3)Running a comparison with and without the 1992 data?

Response: “All” of the birds, including the ones referred to in part 1 of this question, are incorporated into the IPM through the count data. The count data are the number of birds detected each year on the Density Study Area, regardless of whether the birds are marked or unmarked. Doug chose 1993 as the starting year for all of his population trend analyses because that was the first year that we achieved adequate survey coverage of the Density Study Area. As Doug discussed, it is critical that the study area be consistent in size when assessing population trends because the number of birds in the population is a direct function of the size of the study area. The 1992 data are consistent with the hypothesis that spotted owls have evolved a “bet hedger” life history strategy, but so are many other features of their life history (such as long life span, low fecundity). So the 1992 data are interesting but they do not make or break any analysis we do. They are interesting and we are curious, like you, as to why we have not seen similarly high reproduction years since then. However, these data as a single event do not provide insight into changes in owl populations other than to demonstrate that unusually high years of reproduction do occur infrequently.

CA Spotted Owl IT follow up questions by Kim_Ingram, at 1:05 p.m. on 27 August 2012,

The following questions have been submitted by Steve Brink in response to the Owl IT meeting on 8/23/2012:

Q1: Looking again at the Lambda graph, it’s interesting that the downward slope of the line is nearly constant. I should have thought about the 2001 Star Fire when Pat Ferrell, Eldorado NF Contracting Officer, asked a question about it. The Star Fire burned 16,900 acres in Aug-Sept. 2001, about 2,400 acres of which were on the Georgetown Ranger District. Following the fire, the USFS concluded that the two HRCAS, in which PAC055 and PAC075 were located, were essentially destroyed and recommended deleting both PACs from the Forest plan. Further, about 70% of the total acres burned in the Fire were of high severity. So, how is it that the Star Fire had absolutely no affect on the owls ?

Q2: Because soil site classification could be used as a surrogate for the overall “primary productivity” of a forest, will the samples for the control and “treatment” areas be stratified? The premise being that owls in highly productive forests will perform better under both the control and “treatment” conditions, and likewise owls on less productive forests will underperform under control or treatment scenarios.

Q3: It’s still unclear to me why the Team is not opportunistic and looking to tease out why Owls had very high reproductive success in 1992. Using the 1993 data, and not using 1992, doesn’t seem intuitive given Rocky’s premise that CSO’s live a long time and have an evolutionary strategy that is opportunistic for reproduction. How can that be justified?

Q4: Given how robust the IPM is, why wouldn’t Doug include ALL of the owl data that the Team has including: 1) The discrepancies related to the 8 birds that were counted in the occupancy but not as part of the population and likewise the other 4 birds that resisted capture? 2) The 1992 reproduction data since it is congruent with Rocky’s premise that the evolutionary strategy of the owl is to be long lived and be opportunistic for reproduction? 3) Running a comparison with and without the 1992 data?

Steve Brink California Forestry Association

CSO - site occupancy definition by Kim_Ingram, at 11:33 a.m. on 6 February 2012,

Can you provide a "working" definition the researchers are using for spotted owl occupancy. Is it simply occupancy (i.e. owl presence) or is it pair occupancy, or something else? Thank you for your time and consideration with this question. Kevin Roberts Wildlife Biologist Sierra Pacific Industries

The determination for occupancy is the presence or absence of an owl that is corrected for detection probability. It can be a single owl or a pair. Rocky Gutierrez - SNAMP Owl team Kim Ingram - PPT team

USFS response to Bear Grass prescription burn comments & questions by Kim_Ingram, at 1:40 p.m. on 3 November 2011,

Prescribed Burning for Beargrass Enhancement on the Last Chance Project November 3, 2011 "I was forwarded notice about a planned "Bear Grass burn area" at the Last Chance study site. Do you have information about the objectives/prescription for that particular treatment as well as what kinds of monitoring data will be collected pre/post to evaluate the effects? My colleague, Frank Lake, and I are interested in gathering information about fire effects on cultural resources as well as monitoring prescribed fires on the quality of those resources for cultural uses. Thank you, Jonathan Long Pacific Southwest Research Station." Bear grass Xerophyllum tenax, is a fire-tolerant species that needs periodic fire to produce new growth, and is often the first plant to re-sprout after a fire. Low intensity fire eliminates dead, dry blades from the previous year’s growth and encourages supple new leaf growth that is used by traditional weavers to make baskets, hats, and other items. Treatment Objectives 1. Conduct a low intensity burn consuming 80% to100% of the above-surface bear grass leaves to stimulate re-sprouting of new leaves for weaving. 2. Keep unwanted vegetation from encroaching upon the gathering site. 3. Maintain a minimum of forty percent effective soil cover. Fire Behavior Prescription 1. Flame lengths from 3 to 4 feet. 2. Effective wind speed from 6 to 7 miles per hour. 3. Scorch height from 3 to 12 feet. 4. Forward spread rate from 238 to 508 feet per hour. 5. Backing spread rate from 13 to 20 feet per hour. 6. Spotting distance not to exceed 1584 feet. Monitoring On November 2, 2011 2.9 acres of the designated beargrass enhancement area within the Last Chance Integrated Vegetation Management Project were ignited. Preliminary observations indicate that all of the treatment objectives were successfully met. While the Forest Service did not collect pre-burn data for this specific burn area, adjacent unburned fuels are representative of the pre-existing condition. For additional information, contact: Larry Peabody, Fuels Specialist Tahoe National Forest, American River Ranger District 22830 Foresthill Road. Foresthill CA 95631 (530) 367 2224 x 240

Owl team response to population decline question by Kim_Ingram, at 1:25 p.m. on 3 November 2011,

Dear Ms. Dobrovolny:

At the annual SNAMP meeting, I explicitly stated that I did not know what is causing this recent (past 10 years) owl decline. Our research suggests that the decline is real based on two different estimators producing the same result. I was also asked by a participant at the meeting if fuel treatments might be the cause of the decline and I said that I did not know because there were other factors that might be involved such as clear cutting on private land. By logical extension, this would apply to home development as well, as you suggested in your letter. Recall that the owl component of Last Chance includes the entire Eldorado spotted owl density study area, which encompasses a much larger area than Last Chance and has many more owl territories. Because of the uncertainty about the cause of the decline, the owl team has proposed a retrospective study to examine all observable changes in owl habitat that were due to disturbance. Presumably this would allow us to account for different types of disturbance, which would address one of your concerns. Our inference would be restricted to our study areas because we are not measuring change or monitoring owls throughout Eldorado County although our study areas might be a representative sample of this population. In addition, because of severe budget limitations, I doubt that our study could be expanded to include all of Eldorado County.

Sincerely,

R. J. Gutierrez, Professor and Gordon Gullion Endowed Chair in Forest Wildlife Research

CA Spotted Owl population questions by Kim_Ingram, at 9:38 a.m. on 3 November 2011,

The following comments and questions were asked by Lorna Dobrovolny from CA Dept. of Fish and Game:

'I work with Cal Fire foresters on wildlife issues in El Dorado County resulting from forest fuel reduction projects. There are no longer any DFG staff on timber harvesting review teams as a result of state budget cut-backs. California spotted owl has only a Species of Special Concern status. Thus, very limited regulatory protection from projects on private forest lands. I was very interested and concerned about Rocky's findings regarding spotted owls. There has been substantial timber harvesting and population expansion in the early to mid 2000s during the housing boom in El Dorado County. I'm not sure how the SNAMP research can outline a study plan to definitively show that it's the Last Chance fuel break that would be impacting the birds, given a demonstrated existing decline. Do you know how this is going to be accounted for? Also, the USFS and CAL FIRE have given much grant money to forest land owners in the past, mostly to tie together ridgetop fuel breaks for fire prevention. Most of that work was mastication, the result of which may not offer spotted owls suitable habitat."

Thanks for you comments and questions Lorna.

Benefits and sustainability of traditional gathering by Kim_Ingram, at 9:37 a.m. on 8 August 2011,

The following question was asked of the Fire & Forest Ecosystem Health team by Bill Tripp, Eco-cultural Restoration Specialist of the Karuk Tribe, Dept. of Natural Resources:

I would appreciate it if someone could ask if they (the Fire & Forest Ecosystem Health team) are looking at how traditional gathering of Pine roots could potentially contribute to enhanced root production and associated long term below ground carbon storage and expedited growth and associated above ground carbon storage. This would help to provide documentation on the benefits and sustainability of traditional gathering as an ecosystem service and/or resource benefit that can be attributed to management actions where such traditional gathering is occurring or can otherwise be authorized to occur freely. In addition, a similar and connected activity in relation to gathering in Pine stands would be the effects on the quality and quantity of Pine nuts in relation to management actions. It is my understanding that pine nuts were historically a major component of subsistence and trade amongst Native Americans in the Sierra Nevada’s, and pine roots were a primary material in construction of the baskets utilized in the collection of that resource. There are likely additional plants associated with that ecotype that are utilized in the construction of these baskets that should be enhanced in the management of Pine stands and adjacent ecotypes within Sierra Nevada landscapes. The information on resources utilized in the construction of these baskets is likely available from local Tribes, traditional practitioners, tribal elders, and/or museums. Just food for thought.... Thank you,

Bill Tripp Eco-Cultural Restoration Specialist Karuk Tribe Dept. of Natural Resources (530) 627-3446 x3023

Met station concerns and comments by Kim_Ingram, at 11:07 a.m. on 30 November 2010,

The following concerns and comments were brought up from a general public participant after the UC Water Team field trip to Duncan Peak at the Last Chance study site. The UC Water Teams response follows.

"Thanks for allowing me to attend the field trip to Duncan Peak. Good timing....getting up there before this storm. I have one small concern. When there is a lot of snowmobilers out, those poles (met stations) won't be that easy to see. I think that they should be painted a bright orange on top to help for visibility. I mentioned it to the guy who was leading us to the different sensor sites... He said that they (snowmobilers) wouldn't be going that fast & would see them. I don't think that he understands that the extreme snowmobilers around here go very fast on the sides of the mountains, they don't stick to groomed trails; & are out at night sometimes in major storms...not just during the day. Although I agree that someone probably will not be hitting a sensor pole, it wouldn't hurt to make them more visible." Sincerely, Rita Moriarty

"Painting the poles orange would certainly make them more visible to snowmobilers...but my concern is that they would also be extremely visible to everyone else and make them very susceptible to vandalism. I also think that the number of trees surrounding most of our poles would not enable snowmobilers to go very fast around most of our installations. I have seen snowmobile tracks around our previously installed equipment, and they all purposefully avoid the poles. The solar panels on the top make them fairly visible to anyone close by in most conditions. While there are some snowmobilers that do go out at night and in blizzards, that is not recommended by, or for anyone and they do so at their own risk. Furthermore, all terrain covered by snowmobilers is supposed to be reviewed every time before any fast or difficult snowmobiling, due to changes in snow condition, along with any small trees, sticks, logs (or poles!) sticking up that may not be visible at fast speeds or from far away.

I appreciate the concern that Rita has shown for the snowmobilers out there (as we are some of them). We certainly don't want anyone getting hurt or injured from our installations. However, I believe that in most normal conditions our installations will not cause a problem for safe snowmobiling, and we cannot control the actions of those riders that choose unsafe snowmobiling practices."

Thanks, ~Phil Saksa UC Water Team

"Hi All,
I really didn't think about vandalism & wouldn't think that it would be a high priority in winter. Snowmobilers are normally just interested in riding. When you put up any extensions, it might be possible to flag or paint the tops in just the sites that are in the open . That way it isn't allot of extra work for the team. I just mentioned the visibility of poles because you said that if the people on the field trip thought of anything to let you know. I feel that visibility could be important & needed to address that issue." Thanks for listening. Rita Moriarty

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